Normally I'd say to anyone who was trying to emulate a particular film that its tough going and there are too many variables, but since this is about colours only, I'm struggling to give the same advice.
Now I'm not down with Ektar, to me the colours are saturated but also a bit garish, they don't seem to gel well together, so I'm going to use Kodachrome as my film of reasoning.
Kodachrome has a look, a palette of colours that are there generally in all photos shot in a variety of conditions, I don't see why this palette could not be recreated as an action in PS to give a Kodachrome-esq treatment to digitally shot images.
I dunno how to apply that idea to Ektar because Kodachrome colours appear to be global, in that all its colours look treated with Kodachrome magic, where as Ektar seems to render its colours individually, I think that's why I don't like it, they don't appear to be related to each other...I dunno.....that's the way I see it anyway.
I guess I'm saying, if it can be done with Kodachrome, it can be done with Ektar, but it might be a more arduous nut to crack ...:shrug: